1. Field of the Invention
The invention relates to an apparatus for the extrusion coating of a core, especially of an electrical conductor, with a sheathing having at least two layers or strips of different or differently colored materials. The apparatus has at least two separate feed conduits for the plasticized materials and at least two outflow passageways through which the core to be extrusion-coated can pass, and which are intended for the plasticized materials, the said outflow passageways being selectively connectable to the feed conduits via a distributor device.
2. Description of the Related Art
In such apparatus, it has been customary hitherto to provide between the feed conduits and the outflow passageways a cylinder arranged so as to be axially displaceable in a housing which receives the feed conduits and the outflow passageways or the extrusion heads, in which cylinder are arranged essentially mutually parallel conduits and intersecting conduits, via which the feed conduits are connectable selectively to the extrusion heads. At the same time, only half the number of conduits arranged in the cylinder ever receives a plasticized material, whereas the other half of the conduits is inoperative.
This results in the disadvantage that in the inoperative conduits the material remaining therein sets and clogs the conduits, so that they have to be cleaned laboriously, and this entails a very considerable outlay.
An object of the invention is to avoid this disadvantage and to provide apparatus of the type mentioned in the introduction, in which there is no need for cleaning after a change of color or of material.